Myenergi eddi Operation And Installation Manual Download

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Application Examples

Key for Wiring Diagram 4

eddi

device

Mains supply (24hr) (230V AC from B16 circuit breaker
or 13A fused spur)
Hot water cylinder

Heating element (max. 3.7kW)

Isolator (20A double pole)

Relay & Sensor Board (optional add-on for

eddi

)

Temperature probe (type PT1000) (optional)

Mains supply (off-peak timed) (230V AC from B16

circuit breaker or 13A fused spur)

Functional Description

Some electric only households that employ dual tariff billing use two separate electricity meters; one is live for 24 hours and

the other is off-peak timed and bills at the economy rate. Only some appliances are connected to the off-peak supply
(usually water heaters and storage heaters).
This application enables automatic boosting of water heating when the economy tariff is available whilst also using any

surplus generated power to heat the water. Both the top and bottom immersion heaters can use surplus power and be
boosted with peak rate electricity. However, only Heater 1 can be boosted with off-peak electricity (See page 40 if it desired
to have Heater 2 boost using off-peak power).

eddi

is powered from the 24-hour supply and the bottom immersion heater is wired directly to Heater 2 output. During the

economy tariff times, power needs to be drawn from the off-peak tariff meter, to achieve this the top immersion heater is

switched from the

eddi

Heater 1 output and the off-peak supply using both relays of the Relay & Sensor Board (6).

Heater 1 (the top immersion heater) is heated with surplus power until the water at the top of the cylinder is hot and the
thermostat opens, then

eddi

will immediately switch over to Heater 2; heating the bottom of the cylinder. This makes the

most of surplus energy as sometimes there will not be enough to heat the whole volume of the cylinder; it's best to heat a
smaller proportion (i.e. the top) first so there is some usable hot water, rather than a larger volume of warm water.
During heating of Heater 2,

eddi

will switch back to Heater 1 every 15 minutes to check if it can store any more heat.

When the water is fully heated, any surplus power will be exported,

eddi

will switch back the priority heater and check the

lower priory heater every 15 minutes.
If

eSense Input

is set to

Boost Enable 1

, the

BOOST TIMER

screen for Heater 1 will include an option to enable the

boost timer only when the eSense input is live. In the

BOOST TIMER

, the

can be toggled on/off, if

is present, the boost

will activate only when the boost times are valid and the economy rate tariff is available.
Alternatively the eSense input can be used to active the boost whenever the economy tariff rate electricity is available,
regardless of boost times. To do this,

eSense Input

should be set to

Boost 1

. When using this option, the Boost Timer

is not needed.
Installation of the temperature probes (7) is optional; the heaters' mechanical thermostat is used by

eddi

if temperature

readings are not required.
The

eddi

device should be labelled with a “dual supply” warning.

Settings Required

Menu Option